Traders assign nearly equal weight to 16°C and 17°C as the highest temperature in Buenos Aires on August 4 because early-August climatology centers on daytime maxima near 16–17°C under Southern Hemisphere winter conditions of limited solar insolation and prevailing westerly flow. Subtle differences arise from forecast model runs tracking the timing and strength of any passing frontal systems, cloud cover that modulates daytime heating, and local wind speeds that influence mixing within the urban boundary layer. Official Servicio Meteorológico Nacional observations and ensemble guidance show low day-to-day variability, keeping probabilities tightly clustered while acknowledging typical model spread of 1–2°C around the seasonal baseline.